Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd977ad5d0d82c41…

MALICIOUS

PDF

83.3 KB Created: 2021-06-25 14:57:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ccf4fc2325ee47edc6e340ed8e3d285d SHA-1: b6acd391db512eed0720804e488b4c0e6cb3bc2d SHA-256: fd977ad5d0d82c41cae4039ce6b683e6c9dc3ecca854ca23ac298d2b34cbeefa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and UTM parameters in the URLs further supports the link farm and potential SEO manipulation for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://chcial.ru/uplcv?utm_term=surface+area+of+prisms+and+cylinders+formula
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e238f6a260---jojofexevanoki.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072bd4f64eb9---zinuwimozuxusawa.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a285ece99---fesuvutenixalifu.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/708b433b0c89ffb7a71e57e19af0461d/notuwufedow.pdf
    • https://alshamiltrading.com/alshamilfiles/file/33604364253.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/45ae5341011ec0533cf4cd850c27af7a/bifekunabujisalapupamo.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6fc378547---babelekeperixa.pdf
    • http://musorcentrum.hu/files/article/file/melojitedumuzosatawufa.pdf
    • https://horgaszvelem.hu/ckfinder/userfiles/files/5115932319.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3571cc708---kujegerobebovopi.pdf
    • http://goraku-sangyo.com/userfiles/file/63183931043.pdf
    • http://reversetheclocknow.com/ckfinder/userfiles/files/42753995640.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/876ab92abd28b81bb89dbd98a6948807/56330483845.pdf
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/f1b68c3f255fb652fbddf36921c1a7f0/nikame.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5caad1fa7---dogakutitepufa.pdf
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b775b92ea---mazalidipuzop.pdf
    • https://isabellepieman.com/userfiles/file/76007286916.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e01e.bin
9017b5f1408e168e13471ef381bb6642235dbd66d272de85c444dec5b28f12d0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE01E 17068 bytes
font_01_sfnt_off00010cc6.bin
f1fd5418923e97b3a0dbc39fed4bb5aeccce1bb13a0f5e6f8685edbb9b03c194
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC6 10972 bytes
font_02_sfnt_off00012631.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12631 16792 bytes